1, the first digit: the numerical part of the article number indicates the serial number of the paper.

2. Then click (. ): dots are used to separate the parts of the article number.

3. Then there are letters: the letter part of the article number indicates the year and month when the paper was published.

4. Then slash: slash is used to separate the parts of the article number.

5. Tail number: the numerical part of the article number indicates the page number or article number of the paper in the journal.